| From 82cfb90bc99d7b7e0ec62d0505b9d4f06805d5db Mon Sep 17 00:00:00 2001 |
| From: Lai Jiangshan <laijs@cn.fujitsu.com> |
| Date: Thu, 18 Sep 2014 16:49:41 +0200 |
| Subject: drbd: compute the end before rb_insert_augmented() |
| |
| From: Lai Jiangshan <laijs@cn.fujitsu.com> |
| |
| commit 82cfb90bc99d7b7e0ec62d0505b9d4f06805d5db upstream. |
| |
| Commit 98683650 "Merge branch 'drbd-8.4_ed6' into |
| for-3.8-drivers-drbd-8.4_ed6" switches to the new augment API, but the |
| new API requires that the tree is augmented before rb_insert_augmented() |
| is called, which is missing. |
| |
| So we add the augment-code to drbd_insert_interval() when it travels the |
| tree up to down before rb_insert_augmented(). See the example in |
| include/linux/interval_tree_generic.h or Documentation/rbtree.txt. |
| |
| drbd_insert_interval() may cancel the insertion when traveling, in this |
| case, the just added augment-code does nothing before cancel since the |
| @this node is already in the subtrees in this case. |
| |
| CC: Michel Lespinasse <walken@google.com> |
| Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> |
| Signed-off-by: Andreas Gruenbacher <agruen@linbit.com> |
| Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> |
| Signed-off-by: Jens Axboe <axboe@fb.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/block/drbd/drbd_interval.c | 4 ++++ |
| 1 file changed, 4 insertions(+) |
| |
| --- a/drivers/block/drbd/drbd_interval.c |
| +++ b/drivers/block/drbd/drbd_interval.c |
| @@ -79,6 +79,7 @@ bool |
| drbd_insert_interval(struct rb_root *root, struct drbd_interval *this) |
| { |
| struct rb_node **new = &root->rb_node, *parent = NULL; |
| + sector_t this_end = this->sector + (this->size >> 9); |
| |
| BUG_ON(!IS_ALIGNED(this->size, 512)); |
| |
| @@ -87,6 +88,8 @@ drbd_insert_interval(struct rb_root *roo |
| rb_entry(*new, struct drbd_interval, rb); |
| |
| parent = *new; |
| + if (here->end < this_end) |
| + here->end = this_end; |
| if (this->sector < here->sector) |
| new = &(*new)->rb_left; |
| else if (this->sector > here->sector) |
| @@ -99,6 +102,7 @@ drbd_insert_interval(struct rb_root *roo |
| return false; |
| } |
| |
| + this->end = this_end; |
| rb_link_node(&this->rb, parent, new); |
| rb_insert_augmented(&this->rb, root, &augment_callbacks); |
| return true; |